The present invention relates generally to fluid supply methods and apparatus for ink jet printers, and more specifically to a manifold providing fluid connections between a plurality of carriage-mounted ink containers and multiple printheads.
Ink jet printers are well known in the art. The most common type of inkjet printer uses thermal excitation of the ink to eject droplets through tiny nozzles, or orifices, onto a print media. Other ink jet mechanisms, such as the use of piezoelectric transducers or wave propagation as ink droplet generators, are also well understood. With all ink jet technologies, the ink jet pen is typically mounted on a carriage which is scanned across the print media; dot matrix manipulation of the droplets provides alphanumeric character and graphics printing capabilities. To provide a color printing capability, pens for each primary color (cyan, magenta, and yellow) are commonly used, typically in addition to black.
The ink jet pen itself may have a self-contained reservoir for storing ink and providing appropriate amounts of ink to the printhead during a printing cycle. These self-contained pens are commonly referred to in the art as print cartridges. If a reusable, semi-permanent pen rather than a print cartridge is employed, ink is either supplied from a remote, off-axis (or off-board), ink reservoir, or the ink reservoir is mounted on the carriage with the pen.
In the past, printers have been designed with semi-permanent or permanent printheads mounted to a carriage. These printheads would each include a printhead fluid inlet, such as a conduit terminating with a filter. The filters would prevent particles from entering the printheads and would act as check valves, preventing the printheads from depriming. Ink containers containing foam would have fluid outlets for connecting to the filters. Typically, each fluid outlet would include an orifice for receiving a printhead fluid inlet. Thus, the ink containers would mount directly to the carriage and to the printhead fluid inlets.
Ink jet printers are used for a wide variety of printing applications, ranging from simple black-text printing to the production of photographic-quality color prints. For most ink jet printer users, color inks (cyan, magenta, yellow) are used up at a significantly different rate than black inks, with the relative use rate of black and color inks dependent upon the type of user. For example, an office user may use primarily black ink for printing black and white documents. A photographer, on the other hand, may tend to use the color inks at a higher rate. Different configurations of ink reservoirs are therefore desirable for different printing applications.
Although the same basic scanning mechanism and carriage may serve well for many different applications, different printhead configurations are often desirable in different printing situations. The printhead configuration may be optimized for speed, color print quality, cost, or other factors. The office worker may be primarily interested in print speed, while the photographer may be primarily interested in image quality. Other users, such as home computer users, may be primarily interested in the low initial cost of a printer.
Other considerations may dictate a configuration of ink reservoirs which is not conducive to direct fluid connections between the ink reservoirs to the pens. A large reservoir may be used for black ink, and second single reservoir may contain all three primary colors. The ink fluid connections for the color inks will necessarily be relatively close together on the color ink reservoir. The linear spacing of the reservoirs along the scan axis will therefore differ from an optimal spacing of the printheads.
With direct fluid connection between the ink reservoirs and pens, the connection force of the containers can affect alignment between separately mounted printheads, affecting print quality. Over time, as ink reservoirs are used and replaced, the print quality of the printer can degrade.
There is therefore a need for methods and apparatus which allow ink jet printers to be easily configured for different printing applications, and which prevent the removal and installation of ink reservoirs from adversely affecting the alignment of the printheads.
It is an object of the present invention to provide a manifold affording fluid connections between a plurality of carriage-mounted ink reservoirs and multiple printheads, the manifold having ink conduits allowing the spacing, ordering, or number of printheads to differ from the spacing, ordering, or number of ink reservoirs. The manifold also serves to mechanically isolate the printheads from the ink reservoirs, such that replacement of one or more reservoir does not adversely affect the alignment of the printheads.
It is a further object of the invention to provide a printing system adapted to accept different manifold configurations, whereby the printing system may be optimized to a particular use by changing the manifold.
It is a still further object of the invention to provide manifolds configured to supply ink to more than one printhead from a single ink reservoir, allowing for higher printer performance by, for example, allowing the same linear ordering of printhead ink colors in both carriage scan directions.
The present invention also provides a method of configuration a printer system to a particular application by changing the manifold, and methods of manufacturing manifolds and affixing them to printer carriages.